38 research outputs found
The AEDUCATE Collaboration. Comprehensive antenatal education birth preparation programmes to reduce the rates of caesarean section in nulliparous women. Protocol for an individual participant data prospective meta-analysis
Introduction: Rates of medical interventions in normal labour and birth are increasing. This prospective meta-analysis (PMA) proposes to assess whether the addition of a comprehensive multicomponent birth preparation programme reduces caesarean section (CS) in nulliparous women compared with standard hospital care. Additionally, do participant characteristics, intervention components or hospital characteristics modify the effectiveness of the programme? Methods and analysis: Population: women with singleton vertex pregnancies, no planned caesarean section (CS) or epidural. Intervention: in addition to hospital-based standard care, a comprehensive antenatal education programme that includes multiple components for birth preparation, addressing the three objectives: preparing women and their birth partner/support person for childbirth through education on physiological/hormonal birth (knowledge and understanding); building women’s confidence through psychological preparation (positive mindset) and support their ability to birth without pain relief using evidence-based tools (tools and techniques). The intervention could occur in a hospital-based or community setting. Comparator: standard care alone in hospital-based maternity units. Outcomes: Primary: CS. Secondary: epidural analgesia, mode of birth, perineal trauma, postpartum haemorrhage, newborn resuscitation, psychosocial well-being. Subgroup analysis: parity, model of care, maternal risk status, maternal education, maternal socio-economic status, intervention components. Study design: An individual participant data (IPD) prospective meta-analysis (PMA) of randomised controlled trials, including cluster design. Each trial is conducted independently but share core protocol elements to contribute data to the PMA. Participating trials are deemed eligible for the PMA if their results are not yet known outside their Data Monitoring Committees. Ethics and dissemination: Participants in the individual trials will consent to participation, with respective trials receiving ethical approval by their local Human Research Ethics Committees. Individual datasets remain the property of trialists, and can be published prior to the publication of final PMA results. The overall data for meta-analysis will be held, analysed and published by the collaborative group, led by the Cochrane PMA group. Trial registration number: CRD42020103857
Cognitive dysfunction in naturally occurring canine idiopathic epilepsy
Globally, epilepsy is a common serious brain disorder. In addition to seizure activity, epilepsy is associated with cognitive impairments including static cognitive impairments present at onset, progressive seizure-induced impairments and co-morbid dementia. Epilepsy occurs naturally in domestic dogs but its impact on canine cognition has yet to be studied, despite canine cognitive dysfunction (CCD) recognised as a spontaneous model of dementia. Here we use data from a psychometrically validated tool, the canine cognitive dysfunction rating (CCDR) scale, to compare cognitive dysfunction in dogs diagnosed with idiopathic epilepsy (IE) with controls while accounting for age. An online cross-sectional study resulted in a sample of 4051 dogs, of which n = 286 had been diagnosed with IE. Four factors were significantly associated with a diagnosis of CCD (above the diagnostic cut-off of CCDR ≥50): (i) epilepsy diagnosis: dogs with epilepsy were at higher risk; (ii) age: older dogs were at higher risk; (iii) weight: lighter dogs (kg) were at higher risk; (iv) training history: dogs with more exposure to training activities were at lower risk. Impairments in memory were most common in dogs with IE, but progression of impairments was not observed compared to controls. A significant interaction between epilepsy and age was identified, with IE dogs exhibiting a higher risk of CCD at a young age, while control dogs followed the expected pattern of low-risk throughout middle age, with risk increasing exponentially in geriatric years. Within the IE sub-population, dogs with a history of cluster seizures and high seizure frequency had higher CCDR scores. The age of onset, nature and progression of cognitive impairment in the current IE dogs appear divergent from those classically seen in CCD. Longitudinal monitoring of cognitive function from seizure onset is required to further characterise these impairments
Spatial Stereoresolution for Depth Corrugations May Be Set in Primary Visual Cortex
Stereo “3D” depth perception requires the visual system to extract binocular disparities between the two eyes' images. Several current models of this process, based on the known physiology of primary visual cortex (V1), do this by computing a piecewise-frontoparallel local cross-correlation between the left and right eye's images. The size of the “window” within which detectors examine the local cross-correlation corresponds to the receptive field size of V1 neurons. This basic model has successfully captured many aspects of human depth perception. In particular, it accounts for the low human stereoresolution for sinusoidal depth corrugations, suggesting that the limit on stereoresolution may be set in primary visual cortex. An important feature of the model, reflecting a key property of V1 neurons, is that the initial disparity encoding is performed by detectors tuned to locally uniform patches of disparity. Such detectors respond better to square-wave depth corrugations, since these are locally flat, than to sinusoidal corrugations which are slanted almost everywhere. Consequently, for any given window size, current models predict better performance for square-wave disparity corrugations than for sine-wave corrugations at high amplitudes. We have recently shown that this prediction is not borne out: humans perform no better with square-wave than with sine-wave corrugations, even at high amplitudes. The failure of this prediction raised the question of whether stereoresolution may actually be set at later stages of cortical processing, perhaps involving neurons tuned to disparity slant or curvature. Here we extend the local cross-correlation model to include existing physiological and psychophysical evidence indicating that larger disparities are detected by neurons with larger receptive fields (a size/disparity correlation). We show that this simple modification succeeds in reconciling the model with human results, confirming that stereoresolution for disparity gratings may indeed be limited by the size of receptive fields in primary visual cortex
Serotype 3 Experimental Human Pneumococcal Challenge (EHPC) study protocol: dose ranging and reproducibility in a healthy volunteer population (challenge 3)
Introduction: Since the introduction of pneumococcal conjugate vaccines, pneumococcal disease rates have declined for many vaccine-type serotypes. However, serotype 3 (SPN3) continues to cause significant disease and is identified in colonisation epidemiological studies as one of the top circulating serotypes in adults in the UK. Consequently, new vaccines that provide greater protection against SPN3 colonisation/carriage are urgently needed. The Experimental Human Pneumococcal Challenge (EHPC) model is a unique method of determining pneumococcal colonisation rates, understanding acquired immunity, and testing vaccines in a cost-effective manner. To enhance the development of effective pneumococcal vaccines against SPN3, we aim to develop a new relevant and safe SPN3 EHPC model with high attack rates which could be used to test vaccines using small sample size.
Methods and analysis: This is a human challenge study to establish a new SPN3 EHPC model, consisting of two parts. In the dose-ranging/safety study, cohorts of 10 healthy participants will be challenged with escalating doses of SPN3. If first challenge does not lead into colonisation, participants will receive a second challenge 2 weeks after. Experimental nasopharyngeal (NP) colonisation will be determined using nasal wash sampling. Using the dose that results in ≥50% of participants being colonised, with a high safety profile, we will complete the cohort with another 33 participants to check for reproducibility of the colonisation rate. The primary outcome of this study is to determine the optimal SPN3 dose and inoculation regime to establish the highest rates of NP colonisation in healthy adults. Secondary outcomes include determining density and duration of experimental SPN3 NP colonisation and characterising mucosal and systemic immune responses to SPN3 challenge.
Ethics and dissemination: This study is approved by the NHS Research and Ethics Committee (reference 22/NW/0051). Findings will be published in peer-reviewed journals and reports will be made available to participants
Homogenisation of sulphide inclusions within diamonds: A new approach to diamond inclusion geochemistry
Base metal sulphide (BMS) inclusions in diamonds provide a unique insight into the chalcophile and highly siderophile element composition of the mantle. Entombed within their diamond hosts, these provide a more robust (closed system) sample, from which to determine the trace element, Re-Os and S-isotopic compositions of the mantle than mantle xenoliths or orogenic peridotites, as they are shielded from alteration during ascent to the Earth’s crust and subsequent surface weathering. However, at temperatures below 1100 °C some BMS inclusions undergo subsolidus re-equilibration from an original monosulphide solid solution (Mss) and this causes fractionation of the major and trace elements within the inclusions. Thus to study the subjects noted above, current techniques require the entire BMS inclusion to be extracted for analyses. Unfortunately, ‘flaking’ of inclusions during break-out is a frequent occurrence and hence the risk of accidentally under-sampling a portion of the BMS inclusion is inherent in current practices. This loss may have significant implications for Re-Os isotope analyses where incomplete sampling of a Re-rich phase, such as chalcopyrite that typically occurs at the outer margins of BMS inclusions, may induce significant bias in the Re-Os and 187Os/188Os measurements and resulting model and isochron ages. We have developed a method for the homogenisation of BMS inclusions in diamond prior to their break-out from the host stone. Diamonds are heated to 1100 °C and then quenched to chemically homogenise any sulphide inclusions for both major and trace elements. Using X-ray Computed Microtomography (µCT) we determine the shape and spatial setting of multiple inclusions within a host stone and crucially show that the volume of a BMS inclusion is the same both before and after homogenisation. We show that the homogenisation process significantly reduces the inherent variability of in situ analysis when compared with unhomogenised BMS, thereby widening the scope for multiple methods for quantitative analysis, even on ‘flakes’ of single BMS inclusions. Finally we show that the trace elements present in peridotite (P-type) and eclogitic (E-type) BMS are distinct, with P-type diamonds having systematically higher total platinum-group element (particularly Os, Ir, Ru) and Te and As concentrations. These distinctions suggest that the PGE and semi-metal budgets of mantle-derived partial melts will be significantly dependent upon the type(s) and proportions of sulphides present in the mantle source
From Craft to Nature: The Emergence of Natural Teleology
A teleological explanation is an explanation in terms of an end or a purpose. So saying that ‘X came about for the sake of Y’ is a teleological account of X. It is a striking feature of ancient Greek philosophy that many thinkers accepted that the world should be explained in this way. However, before Aristotle, teleological explanations of the cosmos were generally based on the idea that it had been created by a divine intelligence. If an intelligent power made the world, then it makes sense that it did so with a purpose in mind, so grasping this purpose will help us understand the world. This is the pattern of teleological explanation that we find in the Presocratics and in Plato. However, with Aristotle teleology underwent a change: instead of thinking that the ends were explanatory because a mind had sought to bring them about, Aristotle took the ends to operate in natural beings independently of the efforts of any creative intelligence. Indeed, he thought that his predecessors had failed to understand what was distinctive of nature, namely, that its ends work from the inside of natural beings themselves
Aristotle on the Matter for Birth, Life, and the Elements
This essay considers three case studies of Aristotle’s use of matter, drawn from three different scientific contexts: menstrual fluid as the matter of animal generation in the Generation of Animals, the living body as matter of an organism in Aristotle’s On the Soul (De Anima), and the matter of elemental transformation in Generation and Corruption. I argue that Aristotle conceives of matter differently in these treatises (1) because of the different sorts of changes under consideration, and (2) because sometimes he is considering the matter for one specific change, and sometimes the matter for all of a thing’s natural changes. My account allows me to explain some of the strange features that Aristotle ascribes to the matter for elemental transformation in Generation and Corruption II. These features were interpreted by later commentators as general features of all matter. I argue that they are a result of the specific way that Aristotle thinks about the transmutation of the elements
Cornarchy
Undergraduate student, year of graduation: 2020. Major: Experimental and Foundation Studies. Class: Design. Faculty: Martie Holmer.https://digitalcommons.risd.edu/bookcontest3rd2017/1069/thumbnail.jp
Grave To Cradle
10 unnumbered pages : color illustrations. Cover title. Edition of 35, signed and numbered by the artist. Trifold book cover which when opened displays the wingspan of a moth screenprinted on cloth. This book was printed as part of an In Cahoots residency in Petaluma, CA, in October of 2019. It was assembled in Chicago, IL, in February of 2021 --Colophon. Inspired by real-life bagworms, insects that construct different cocoons based on the materials available in their environments, and an actual cemetery in Petaluma, CA, \u27Grave to Cradle\u27 is a short magical realism story about insects that synthesize not only physical objects found on graves (flowers, ribbons, cacti) but also the memories and emotions of the deceased into dense, crowded cocoons. The lives of a murderer, a young girl, and a married couple are woven into cradles that give new life to the bagworm moths that emerge from them --Artist\u27s statement, Vamp & Tramp Booksellers website (accessed April 28, 2021). Center pages foldout into one large color print. Sewn binding with foldout. Library has copy no. 2.https://digitalcommons.risd.edu/specialcollections_artistsbooks/1327/thumbnail.jp